Steam generator



Aug. 5, 1941. F. HOLZKNECILIT- STEAM GENERATOR Filed April 13. 1939 2 Sheets-Sheet l 1941. F. HOLZKNECHT 2,251,280

STEAM GENERATOR Filed April 13, 1939' 2 Sheets-Sheet 2 ghvumviom 6] i: 253 suF PLY Fez Hbag Patented Aug. 5, 1941 rarest STEAM GENERATOR Application April 13, 1939, Serial No. 267,649

2 Claims.

This invention relates to steam generators and it consists in the constructions, arrangements and combinations herein described and claimed.

It is an object of the invention to provide a generator in which a down draft of fire through fire tubes is provided, reducing heat lossesthrough trapping of lighter gases which ordinarily pass to the flue of a generator,

It is also an object of the invention to provide a generator in which there is no turbulence of the water being heated due to the down flow of fire through the fire tubes of the generator.

t is a still further object of the invention to provide a generator in which scaling of the boiler is eliminated, since the impurities are caused to pass to a mud sump in the base of the generator.

Additional objects, advantages and features of invention will be apparent from the following description considered in conjunction with the accompanying drawings, wherein Figure 1 is a top plan view of the generator.

Figure 2 is a cross section on the line 2-2 of Figure l.

Figure 3 is a top plan view of the float bearing employed in the generator.

Figure 4 is an enlarged detail of the relief valve.

Figure 5 is an enlarged fragmentary detail of the upper portion of the generator.

Figure 6 is a horizontal cross section through the generator.

Figure 7 is a cross section on the line 1--'.i of Figure 1, and

Figure 8 is a diagrammatic view illustrating the electrical circuits for actuating water control valves and ignition means of the generator.

Referring to the drawings, there is illustrated a generator indicated by the reference character it which comprises an annular drum l l, the lower end of which is provided with a downwardly extended conical base l2, and the upper end is provided with an upwardly directed conical head 63. It should be noted that the drum H extends above the head I3, as indicated at it.

The base I? and the head it are connected by a plurality of fire tubes Id, arranged in circumferential rows as clearly shown in Figure 6. The base i2 has a downwardly extended collar it, interiorly threaded for reception of a sump valve E5. The head it has integrally formed therewith an upstanding collar ii, the latter being axially aligned with the collar it. As may be seen from Figure 2, the innermost tubes it are positioned just outwardly of the peripheries of the collars l5 and I1, thereby providing a central unrerestricted area it for a purpose as will appear hereinafter, V

A casing I9 is fixed to the base l2, extending circumferentially therearound and includes a pipe 28, at the outer end of which there is suitably mounted an inductor blower 2|, driven by means of a motor 22.

The tubes Ml open upon the casing l9 and it will therefore be seen that with the blower Ed in operation, a down draft through the tubes will be created, as will be dealt with in greater detail hereinafter.

Within the collar l'l there is snugly fitted a sleeve 23 having a plurality of inwardly directed radial fins 24, the lower ends of which are provided with stop means 25. If desired, the collar i? may be recessed as at 25 for support of the sleeve.

Extended between a pair of fins 2 3 there is a bearing member 2! consisting of an axial hearing sleeve 28 from which oppositely extended arms 29 are provided, the latter being formed with forked ends 3% for engagement with respective opposed fins of the sleeve. The upper ends of the fins 2% are provided with struck out tongues 31 preventing upward movement of the bearing member 27. Other stop means may be provided, however.

The bearing sleeve 23 reciprocately supports a stem 32, and upon the lower threaded end there is engaged a float 3?. The float 33 may be adjusted upon the threaded stem to accommodate various desired water levels in the generator. The upper end of the stem terminates in a head 3% operable between a pair of electrical contacts, now to be described.

The upper end of the collar H is exteriorly threaded to receive a flanged collar 35, the latter being suitably apertured and tapped to receivethe bolts 36 extended through apertures of a closure plate 37 for the collar ii. The plate 3'! has an annular tapered flange 38 for seating engagement with a similarly formed seat of the upper end of the collar i1, whereby a steam-tight connection may be formed, it being understood that by tightening the bolts 36 draw the flange 38 into snug and tight engagement with the upper end of the collar l l.

The closure plate 31 has insulatedly mounted therein a pair of contacts 39 and it, the first named affording control of the low level of water and the latter the high level of water within the generator, as will be apparent as the description proceeds, and reference is now made to Figures 5 and 8 of the drawings. It will be noted that the contact 39 is positioned below the level of the contact 45, and that the head 34 of the stem of the float is movable upwardly and downwardly between the contacts and that the contacts will be engaged by the head in either of its extreme movements.

As may be seen in Figure 8, lowering of the float 33 will cause engagement between the contact 3-9 and the head 34 completing the electrical circuit to an electromagnet 4| for actuating a valve 42 associated with the inlet 43, admitting water to the pump 44 for passage to the generator it], by way of a pair of branched contacts 45 discharging into a lower portion of the generator. The flow of water continues until the float t3 rises to such extent that the head 34 disengages the contact 39. However, should passage of water into the generator continue, through leakage or otherwise, the float will be caused to rise further, engaging the contact 40 when the electromagnet 45 is energized to actuate the bypass valve il which is normally closed.

The inlet conduits 45 will include one-way valves 46 admitting water to the generator I0, but opposing the return of water when the bypass valve is open. It will thus be seen that the water from the condenser line 48 will by-pass through the valve 41, the pipe 49 to the inlet side of the pump 44. This circulation of water is possible since the steam pressure in the generator maintains the valves 4% closed to passage of Water to the generator.

In the present instance, springs 585ll retract the core of the electromagnets 41-46, and the electromagnets are energized through a source through leads 52-53.

A relief valve 54 is mounted upon the elbow 55, the latter having a threaded nipple for connection of a pipe leading to the point of use. As shown, the elbow comprises an apertured flange 56 seated around a reduced nipple 51 of the elbow, the opposite end of the nipple having a tapered portion 58 complemental to a seat in the plate 31. The flange 56 has circumferentially spaced apertures through which tie bolts 59 are extended, the latter being threadedly engaged in apertures 5i? of the plate 31. It will thus be seen that the elbow 55 may be securely mounted against leakage of steam. The relief valve 54 comprises a spring-seated valve 54 and the housing therefor preferably has downwardly opening vents 6!.

At a suitable point above the upper wall l3 there is provided a lining 62 of fire brick or clay, the latter having a vertical wall 63 for anchorage to the upstanding wall l3 as clearly shown in Figure 2, the lining being extended upwardly at an angle abutting the sleeve I1. Thus a fire chamber 54 is provided immediately above the tubes l4.

Between the uppermost portion of the lining E2 and the junction of the sleeve I! with the top wall It, a plurality of heat absorbing fins 65 are provided, in the present instance being shown as having a collar 66 circumscribing the sleeve l? and a right angular annular flange 61.

The fins as are arranged in superposed relation, permitting ready installation and preferably will be provided with a high polish and finish as will the lining 62, in order to obtain advantage of all heat from the products of combustion.

A dead air space 68 is provided outwardly of the lining 62 by the provision of a cap 69 entirely enclosing the lining, the cap being hermetically sealed to the outer wall l3 as clearly shown in Figures 2 and 7.

An outer casing 10 encircles the generator and the top thereof, the casing being spaced therefrom and open at the bottom to permit air to space therearound and supplying air to the burner indicated at l I.

Preferably, the burner II will direct its flame at a tangent to the fire chamber 64 so that the flame will be caused to follow a path circumierentially above the tubes l4 insuring an even distribution of fire above the tubes, and to assist this action, an arcuate deflector plate 12 is fixed to the inner wall of the generator, being positioned slightly in advance of the inlet 12 of the burner.

Means for igniting the fuel initially is provided, in the form of a spark plug 13 suitably mounted in the walls defining the chamber 64, and as may be seen from Figure 8, the plug is electrically connected with the battery through a lead 14. A switch 15 is also connected in the lead 14, as is a high tension coil 16.

In use, fuel under pressure is supplied to the burner ll, being discharged into the chamber 54 where it is ignited by the spark plug 73 upon closing of the switch 15. After initial igniting of the fuel, the circuit to the plug is broken through manipulation of the switch, the fire continuing so long as fuel is fed to the burner. The inductor blower 2| being in operation, a suction is created in the tubes l4, drawing the flame downwardly therethrough and since water in the generator is in direct contact with the tubes, the water will be rapidly heated and generated into steam, the latter passing upwardly and outwardly through the elbow 55 to a point of use. It will be noted that the upper portion of the body of water will be first heated, effecting a quick generation of steam, and this also prevents turbulence of the water, permitting ready and quick deposit of sediment to the inclined base i2 where the sediment will discharge to the sump, valve i6. Obviously, since the sediment is quickly removed from the water, deposits on and scaling of the tubes l4 and the generator Walls will be prevented.

When the water level in the generator has lowered to a point where replenishment is necessary this is effected through lowering of the float, as has already been explained, and similarly the float controls the closing of the supply of water to the generator.

While I have specificall described the generator, this is by way of illustration only, and I consider as my own all such modifications in structure as fairly fall within the scope of the appended claims.

I claim:

. l. A steam generator comprising a boiler having side walls and a conically shaped lower head and a similarly shaped upwardly disposed upper head, a plurality of circumferentially spaced fire tubes connected between the upper and lower heads, said tubes being positioned to provide an unrestricted central area, water inlet means opening into the boiler, said upper and lower heads having an axial sleeve, a sump valve connected with the sleeve of the lower head, a steam outlet fitting connected with the sleeve of the upper head, a cap disposed above the upper head and connected with the walls of the boiler defining a combustion chamber, a, plurality of annular fins on the sleeve of the upper head positioned within the combustion chamber, a secnd cap with depending walls spaced from the first cap to provide an outer casing surrounding the generator and defining an air space, the casing being open at the base to provide passage of air therearound, said combustion chamber having a tangentially positioned fuel port in the first cap in communication with the space defined by the outer casing, a fuel burner operativelyassociated'with the fuel port and said air space, an arcuate deflector plate in the combustion chamber whereby to deflect the flame from the burner ciroumferentially of the chamber, and an inductor blower operatively connected with the lower ends of the fire tubes whereby to draw the fire downwardly therethrough.

2. A steam generator comprising a boiler having side walls and a comically shaped lower headand a similarly shaped upwardly disposed upper head, a plurality of circumferentially spaced fire tubes connected between the upper and lower heads, said tubes being positioned to provide an unrestricted central area, water inlet means opening into the boiler, said upper and lower heads having an axial sleeve, a sump valve connected with the sleeve of the lower head, a

steam outlet fitting connected with the sleeve of the upper head, a cap disposed above the upper head and connected with the walls of the boiler defining a combustion chamber, a plurality of annular fins on the sleeve of the upper head positioned within the combustion chamber, walls forming a dead air space between the combustion chamber and the cap, an outer casing surrounding the generator but open at the base to provide a space for passage of air therearound, a fuel port tangentially opening upon the combustion chamber through said cap and in communication with the space defined by the outer casing, a fuel burner operatively associated with the fuel port and the air space, a deflector plate in the combustion chamber having an arcuate portion extended in the direction of the flame from said burner whereby to deflect the flame from the burner circumferentially of the chamber, a housing enclosing the lower ends of the fire tubes and an inductor blower operatively connected with the housing whereby to draw the fire downwardly through the tubes.

FELIX HOLZKNECHT. 

